With the new release of the Android Testing Support Library 1.0, there’s a GrantPermissionRule that you can use in your tests to grant a permission before starting any tests.
@Rule public GrantPermissionRule permissionRule = GrantPermissionRule.grant(android.Manifest.permission.ACCESS_FINE_LOCATION);
Kotlin solution
@get:Rule var permissionRule = GrantPermissionRule.grant(android.Manifest.permission.ACCESS_FINE_LOCATION)
@get:Rule
must be used in order to avoid java.lang.Exception: The @Rule 'permissionRule' must be public.
More info here.